a-a a-b a-i aaa aab aad aai aap aar aas ab- aba abb abd abi abp abr abs ad- ada adb add adi adp adr ads ai- aia aib aid aii aip air ais ap- apa apb apd api app apr aps ar- ara arb ard ari arp arr ars as- asa asb asd asi asp asr ass b-p baa bab bad bai bap bar bas bba bbb bbd bbi bbp bbr bbs bda bdb bdd bdi bdp bdr bds bi- bia bib bid bii bip bir bis bpa bpb bpd bpi bpp bpr bps bra brb brd bri brp brr brs bsa bsb bsd bsi bsp bsr bss daa dab dad dai dap dar das dba dbb dbd dbi dbp dbr dbs dda ddb ddd ddi ddp ddr dds di- dia dib did dii dip dir dis dpa dpb dpd dpi dpp dpr dps dra drb drd dri drp drr drs dsa dsb dsd dsi dsp dsr dss i-d ia- iaa iab iad iai iap iar ias iba ibb ibd ibi ibp ibr ibs ida idb idd idi idp idr ids iia iib iid iii iip iir iis ipa ipb ipd ipi ipp ipr ips ir- ira irb ird iri irp irr irs is- isa isb isd isi isp isr iss p-p paa pab pad pai pap par pas pba pbb pbd pbi pbp pbr pbs pda pdb pdd pdi pdp pdr pds pia pib pid pii pip pir pis ppa ppb ppd ppi ppp ppr pps pra prb prd pri prp prr prs ps- psa psb psd psi psp psr pss ra- raa rab rad rai rap rar ras rba rbb rbd rbi rbp rbr rbs rda rdb rdd rdi rdp rdr rds ria rib rid rii rip rir ris rpa rpb rpd rpi rpp rpr rps rra rrb rrd rri rrp rrr rrs rsa rsb rsd rsi rsp rsr rss saa sab sad sai sap sar sas sba sbb sbd sbi sbp sbr sbs sda sdb sdd sdi sdp sdr sds sia sib sid sii sip sir sis spa spb spd spi spp spr sps sr- sra srb srd sri srp srr srs ss- ssa ssb ssd ssi ssp ssr sss